On this day -- dedicated to giving thanks we'll introduce you to a young man whose story is a testament to the power of friendship. And the strength of the spirit his name is Darius Weems in his life has been an incredible and some might say it nearly impossible journey. He lives each day with a devastating disease to -- muscular dystrophy and yet. He's one of the most positive and inspiring people -- government. Bush didn't -- an unexpected. -- It's hard to believe all of this started as a road trip between friends -- makes. -- -- For seven years and many many miles later. A lesson about life. From a guy who knows firsthand how precious every game. -- -- China mean they have. Very happy -- -- -- -- -- the fab food bringing -- the house on this Sweeney. -- -- But -- don't seem to amuse me. Like kids from Athens Georgia in a wheelchair in the middle of main. Right there. And they are going out of their minds. From town to town had a pinch -- thereafter. Come maybe reality these kids are going -- -- -- a -- -- Google peak demand of -- for a. Various inventiveness to spend a couple of days and -- believed to. Clinton visits schools around the country -- the kids to believe. If he can -- his -- Second then. -- suffers from machine muscular dystrophy and genetic disorder that affects 13500. -- of them. Resulting in the disintegration of muscle tissue. Legs no arms -- -- and eventually sell with the muscles that surround the heart. In the US the average -- -- stuffed bird dies my twenty the course. He's killed his older brother at nineteen. Darius is 22. And he is truthful to fight with everything he's got. -- probably. When his live -- -- slow down and see him leave to work on that changed my life. Trip it's been a slow but steady progression he could -- when he was a kid but -- Randy action nine he transition to walker. A wheelchair came at age twelve. Now he can only -- fingers and feet. But of course is -- works just fine on that I spends a lot of his time writing grant. But it's not about this in my life. There. We first met -- -- back in 2007. When my -- then Nightline colleague Martin Bashir spent some time within. Morton had a particularly interest in Darius. Cantons. Disease my brother died when he was 29 -- brother died. When he was nineteen. Do you worry at all about the future the more that you appreciate your life the more that you give out Logan smalley -- Darius was a special kid. Bennett counselor at a camp Darius -- brother Mario attendant there. Before Mario died he asked Logan to watch over his little brother tell it first -- -- that maybe dairy issue go away. It was Darius. His mom and myself and we're watching T. And we jokingly said you know we should get your wheelchair customized on MTV and about thirty seconds faster than we said. Well this is the real story we should really still missing and make a movie to raise awareness for addition muscular district it was so at fifteen Darius took an extraordinary journey across. Its movie and and a -- -- We have found this -- -- -- person. -- professional life from my ideals and just the same sort of people I got him. The journey became the film Darius goes west. It was the first time Darius had -- -- left his hometown. Of Athens Georgia. How did -- talk your mother -- it Muslims are. She's been on that you know I knew it was a pretty crazy idea if you think mostly -- -- and our team. -- on millions of jobs. They traveled to the Grand Canyon and acknowledging -- war where the have you brought tears to resign. Him. Into the ocean. Darius stood up for the first time in almost four years. Did he never did in his wheelchair. But the trip was the success. Good. Journey has turned to learn about attitude about giving thanks and about giving back. And about two young men who couldn't be more different on the outside the -- like -- inside. What do you think you've given Logan are -- -- give each other things -- -- him. Actually taking on the -- -- Watching over -- -- brother passed away low we seen any growth plan announced -- he has go to the man that I am now so. I'd definitely thing. -- -- -- -- -- -- -- So last areas where he felt he had given -- what if -- given him. There's not have a mutual respect for each other I think it's some strange mixture. Brotherhood and parenthood old married couple best friends -- Our relationship -- again you know I love them more than anybody and we just have so much fun together and and it feels really good because it feels like we -- The -- religious strength of the film the power of their friendship. Power of their belief in one another bite off their SEC -- -- samba. Through the years Darius and Logan have also given each other a lot of laughs -- of the most poignant moments in the film happens by accident. Visiting the San Francisco zoo's dairy uses -- dare him to eat this spoonful of mousavi. Known to be super hot but something he's never heard of before and that he clearly can't pronounce. They didn't elect him Ethan Yugoslavs saw it is clear thinking it. Over. With -- -- He takes the challenge. -- don't think it's getting. When I saw the film and and and that -- starts to play. I was very unhappy that they were having you do that. Now all I felt like they were picking on -- and then as I watched it unfold. I realize that they were treating you just like everybody else. When we lose tram goes elated and I -- in June. -- name's -- can only answer right there -- thank you -- -- data shows a good message in history and we like loose. He's just one of the guys and it's sad -- perhaps more than any of that the captain takes the kids and this means they traveled to. Infected in the popular way to raise money for medical research would machine. -- in the hunt for who -- high school students than having their own -- lobbied challenge. Darius Miles have beaten. -- so far Darius -- raised more than two million dollars for the -- much of it to the sound of laughter. So what was cited in the movie at least -- -- what life was like. Are you physically a little bit worse than that well I was saying life is aquariums -- a -- -- most of -- -- -- on. Doing in making a movie on over the years I kind of do real lack heart problem I didn't -- soldier and to keep mock -- function race through. You don't really years and we're getting close to a two deafening on May actually be -- form in the clinical trial. And John Hopkins and never did I think in my life time I was -- be allowed war. -- and they would -- in the clinical trial.

This transcript has been automatically generated and may not be 100% accurate.

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